PSAT Math Multiple-Choice Question 296: Answer and Explanation

Question: 296

In a restaurant's kitchen, c cakes are made by adding s cups of sugar to a mix of eggs and butter. If s = 3 c + 5, how many more cups of sugar are needed to make one additional cake?

• A. 0
• B.
• C. 1
• D. 3

Correct Answer: D

Explanation:

D

Difficulty: Medium

Category: Word Problems

Strategic Advice: Pick a number for c to see how many cups of sugar will be needed, then pick another number for c to see how the number of cups of sugar changes.

Getting to the Answer: Pick a number for c; let's say c = 2. This means that 3(2) + 5 = 11 cups of sugar are needed for two cakes. Now, try c = 3: 3(3) + 5 = 14 cups of sugar needed for 3 cakes. To go from 2 cakes to 3 cakes, 3 additional cups of sugar were needed, which is (D). You can try c = 4 to confirm: 3(4) + 5 = 17, which is another 3 cups of sugar.